DESCRIPTION The bsearch() function searches an array of
nmemb objects, the initial member of which is pointed to by
base, for a member that matches the object pointed to by
key. The size of each member of the array is specified by
size.

The contents of the array should be in ascending sorted
order according to the comparison function referenced by
compar. The compar routine is expected to have two arguments
which point to the key object and to an array member, in
that order, and should return an integer less than, equal
to, or greater than zero if the key object is found, respec-
tively, to be less than, to match, or be greater than the
array member.

RETURN VALUE The bsearch() function returns a pointer to
a matching member of the array, or NULL if no match is
found. If there are multiple elements that match the key,
the element returned is unspecified.

CONFORMING TO SVr4, 4.3BSD, POSIX.1-2001, C89, C99.

EXAMPLE The example below first sorts an array of
structures using qsort(3), then retrieves desired elements
using bsearch().